1. Technical Field
The present invention relates to a fixing device and an image forming apparatus.
2. Related Art
Conventionally, in image forming apparatus such as printers and copiers that perform image formation using the electrophotographic system, a fixing device is utilized which passes a toner image that has been transferred onto recording paper through a nip portion formed by a fixing roller or a fixing belt disposed with a heat source such as a halogen heater and a pressure roller and which melts the toner by the action of heat and pressure to fix the toner image to the recording paper.
As the heat source, there are fixing devices of the electromagnetic induction heat generating system using a coil that generates a magnetic field as a result of electrical power being supplied thereto and a heat generating body that generates heat as a result of an eddy current being formed by electromagnetic induction of the magnetic field.
In fixing devices of the electromagnetic induction heat generating system, in order to effectively utilize the magnetic field generated by the coil, there is a fixing device where a core material and a magnetic circuit forming member configured by a magnetic material are disposed in a position adjacent to the coil so that a magnetic circuit is formed between them and the coil magnetic field.